1. Field
Apparatuses and systems consistent with exemplary embodiments relate to a backlight unit and a two-dimensional (2D) and three-dimensional (3D) image display system including the same.
2. Description of the Related Art
In general, 3D images are generated by the principle of stereo vision of both eyes. Since both eyes are separated about 65 mm from each other, binocular parallax occurs as the most important factor in a stereoscopic feeling. 3D image displays generally include 3D image displays requiring glasses and 3D image displays not requiring glasses. 3D image displays not requiring glasses obtain 3D images by separating right and left images from each other. 3D image displays not requiring glasses use a parallax barrier method or a lenticular method.
In the parallax barrier method, images to be observed by the right and left eyes are alternately printed or developed as a photo having longitudinal patterns and are observed using a very thin longitudinal lattice row, e.g., a barrier. In this way, a longitudinal pattern image observed by a left eye and a longitudinal pattern image observed by a right eye are divided by the barrier into parts, and images having different view points are observed by the right and left eyes as a stereoscopic image.
In the lenticular method, images corresponding to the right and left eyes are disposed on a focusing surface of a lenticular lens and are observed using the lenticular lens, and then the images are divided according to the right and left eyes according to the characteristics of the lenticular lens so that a stereoscopic image can be formed. The lenticular method has a higher light efficiency than the parallax barrier method. On the other hand, since lenticular lenses are disposed at the front of a display device, external light is reflected, thereby reducing a contrast ratio.
In addition, a narrow viewing zone is formed by the parallax barrier method and the lenticular method, and thus only one person can watch an image at the center of the image.